Accuracy of partially and fully guided surgical techniques for immediate implant placement: An in vitro assessment

STATEMENT OF PROBLEM

Optimal implant positioning is essential to achieving predictable results. Computer-guided surgery has been reported to be an accurate technique for implant placement in healed sites, but the accuracy of guided techniques for immediate implant placement into fresh sockets is still unclear.

PURPOSE

The purpose of this experimental randomized split-mouth study in pig jaws was to determine the accuracy of partially and fully guided surgical techniques for immediate implant placement into fresh sockets and to compare 2 different methods of implant position deviations analysis.

MATERIAL AND METHODS

Twenty implants were installed in 10 pig jaws using 2 different techniques: partially guided (n=10) and fully guided (n=10). Cone beam computed tomography and digital scanning were performed before and after the surgical procedure to plan the virtual implant position and fabricate the surgical guide, as well as to determine implant position deviations. Two methods were used to evaluate implant deviations: tomographic and digital scanning. The Shapiro-Wilk test of normality was used. Deviation comparisons were carried out by using paired t tests (α=.05), and intraclass correlation coefficient (ICC) was computed to assess the agreement between the 2 methods of implant deviation analysis.

RESULTS

In the tomographic analysis, the partially guided technique resulted in significantly higher global apical and lateral coronal deviations (2.25 ±0.59 mm; 0.96 ±0.55 mm) than fully guided (1.52 ±0.89 mm; 0.75 ±0.52 mm) (P<.01 and P<.05, respectively). The analysis performed using digital scanning showed significantly higher angular, global apical, and lateral apical deviations in the partially guided (6 ±3.28 degrees; 2.49 ±1.03 mm; 2.16 ±1.07 mm) technique than in the fully guided (3.32 ±1.84 degrees; 1.5 ±0.58 mm; 0.98 ±0.67 mm) (P<.05). An ICC of 0.522 between the 2 methods of implant deviation analysis was obtained.

CONCLUSIONS

The partially guided technique was less accurate than the fully guided technique for immediate implant placement into fresh sockets. A moderate concordance was observed between cone beam computed tomography and digital scanning analyses, suggesting that more studies are required to validate and to define the most reliable method of measuring implant deviation.

Effect of osseodensification on the increase in ridge thickness and the prevention of buccal peri-implant defects: an in vitro randomized split mouth pilot study

BACKGROUND

Implant installation with conventional drilling can create buccal bone defects in areas of limited ridge thickness. Implant installation with osseodensification may aid in preventing buccal bone defects in these situations. This in vitro pilot study evaluated the impact of osseodensification on the increase in alveolar ridge thickness and the prevention of buccal peri-implant defects.

METHODS

Ten fresh pig mandibles with limited bone thickness were selected for use in an experimental randomized split mouth pilot study. Two site-preparation protocols were used: conventional drilling with cutting burs (CTL, n = 10) and osseodensification with Densah® burs (OD, n = 10). After implant bed preparation, 20 implants (4.5 × 10 mm) were placed in the prepared sites and the insertion torque was recorded. Clinical and photographic analysis evaluated ridge thickness and the extent (height, width, and area) of bone defects in the buccal and lingual bone walls following implant placement. Three-dimensional measurements were performed using STL files to analyze the increase in buccal ridge thickness following site preparation and implant placement. The height of the buccal bone defect was considered as the primary outcome of this study. Defect width, area, implant insertion torque, and linear buccal ridge increase after implant site preparation and installation were also assessed. Non-parametric evaluations were carried out with the Mann-Whitney test to verify intergroup differences.

RESULTS

There was no statistically significant difference between groups in the baseline ridge thickness. OD presented a significantly higher insertion torque, associated with reduced buccal and lingual bone defect width, in comparison to CTL.

CONCLUSIONS

The increase in buccal ridge thickness after site preparation and implant placement was significantly higher in OD compared to CTL. Osseodensification increased the ridge thickness through expansion and reduced buccal bone defects after implant installation.

AB1189 THE RISK OF FLARE UP FOLLOWING nSARS-CoV2 VACCINE IN INFLAMMATORY ARTHRITIS

Background

As autoimmune phenomena following anti-nSARS-CoV2 vaccine was reported in the healthy population, there is increasing concern in patients with inflammatory joint diseases regarding possible side effects and disease flare-ups.

Objectives

We set out to evaluate the possible risk of disease exacerbation and the predisposing risk factors for the flare up.

Methods

This is a single center prospective cohort study, enrolling patients attending Arthritis Clinic at San Bortolo Hospital, during a follow-up of 12 months. All patients, after obtaining informed consent, answered a 24-item questionnaire including information about nSARS-CoV2 infection, vaccination, disease activity, ongoing treatment, vaccine side effects, disease flare up and need to change therapy.

Results

A total of 109 patients, 60 (55.1%) females and 49 (44.9%) males with a mean age of 60.1 years ±12.6 SD were enrolled. Forty-three (39.5%) were affected by rheumatoid arthritis, 43 (39.5%) from psoriatic arthritis and 23 from anchylosing spondylitis. There were 19 (17.43%) nSARS-CoV2 infection, of them 3 (15.8%) need hospitalization. Ninety-five (87.2%) receive at least one shot of nSARS-CoV2 vaccine, of these 78 (82.1%) got three shots of vaccine. Vaccine-related side effects were reported in 36 (37.9%), of these 15 (41.7%) have fever, 14 (38.8%) arthralgia and 29 (80.5%) fatigue. No patients required medical attention. Twenty (21.05%) of patients who receive at least one vaccine shot experienced a flare up. Nine (45%) need to change therapy. The risk of flare up was significantly associated with low disease activity/active disease in the last 12 months, p=0.009; OD 4.0; 95% CI: 1.5-11.3.

Conclusion

Overall, the nSARS-CoV2 vaccine is well tolerated in patients with inflammatory arthritis. The risk of disease flare is associated with active disease within the past 12 months. According to our results, the patients affected by inflammatory arthritis in sustained remission have no reason to hesitate to get the nSARS-CoV2 vaccination.

Disclosure of Interests

None declared

Flapless Guided Implant Surgeries Compared with Conventional Surgeries Performed by Nonexperienced Individuals: Randomized and Controlled Split-Mouth Clinical Trial

PURPOSE

The study aimed to evaluate the outcomes of flapless guided surgery related to surgery, patient, operator, assistant, and advisor, comparing it with conventional surgery performed by undergraduate students who had never placed implants in patients.

MATERIALS AND METHODS

A randomized controlled split-mouth clinical trial was carried out. Ten patients with bilateral mandibular posterior tooth loss received an implant on each side with conventional flap surgery or flapless guided surgery that was performed by undergraduate students. Surgery time, pain, patient satisfaction, quantity of consumed medications, time of procedure, ease of procedure, anxiety, and stress were assessed.

RESULTS

Conventional surgery showed statistically significantly inferior results compared with flapless guided surgery in terms of procedure time (56 minutes, 36 seconds ± 8 minutes, 38 seconds vs 30 minutes, 1 second ± 6 minutes, 2 seconds), consumption of analgesic medications (49 tablets vs 15 tablets), intraoperative (1.75 ± 1.56 vs 0.65 ± 0.64) and postoperative pain (4.62 ± 2.17 vs 1.17 ± 0.72), and operator anxiety (4.76 ± 1.66 vs 3.47 ± 1.50), respectively.

CONCLUSION

Flapless guided implant surgeries performed by individuals with no previous clinical experience showed reduced surgery time and delivered better patient-reported outcomes both in the intraoperative and postoperative periods; reduced medication consumption; and showed better results in the operator and assistant perspectives.

Emergency 3-Dimensional-Printed Devices for Splitting Ventilators in Lungs With Different Compliances: An In Vitro Study

Ventilator shortages occurred due to the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). This in vitro study evaluated the effectiveness of 3-dimensional (3D)-printed splitters and 3D-printed air flow limiters (AFL) in delivering appropriate tidal volumes (TV) to lungs with different compliances. Groups were divided according to the size of the AFL: AFL-4 was a 4-mm device, AFL-5 a 5-mm device, AFL-6 a 6-mm device, and no limiter (control). A ventilator was split to supply TV to 2 artificial lungs with different compliances. The AFL improved TV distribution.

Improving the bonding stability between resin cements and zirconia-based ceramic using different surface treatments

PURPOSE

To evaluate the effects of airborne-particle abrasion with alumina particles or silicamodified alumina particles on the bond strength between zirconia and conventional MDP-based (Ph; Panavia F 2.0, Kuraray) or self-adhesive (SA; RelyX U200, 3M ESPE) resin cements.

MATERIALS AND METHODS

Five surface treatments were evaluated: C = no surface treatment; AB = airborne-particle abrasion with alumina particles (BIO-ART Dental Supplies and Equipment); ABP = AB combined with MDP-based primer (Alloy Primer, Kuraray); SS = airborne-particle abrasion with silica-modified alumina particles (CoJet, 3M ESPE) combined with silane (RelyX Ceramic Primer, 3M ESPE); and SSP = SS combined with MDP-based primer. The surface roughness (Ra) of the airborne particle-abraded samples (n = 5) was measured by a contact profilometer (Mitutoyo Surftest SJ-401, Mitutoyo). Cylinders of the resin cements tested were bonded to the surface-treated zirconia. The microshear test was performed by the application of a load with a wire loop parallel to the adhesive interface until debonding of the resin cement cylinders. The microshear bond strength (μSBS) of the samples was measured before and after being subjected to thermocycling (TC; 5°C to 55°C, 60 seconds dwell time for 3,000 cycles; MSCT, Marcelo Nucci). One-way (Ra) and two-way (μSBS) analysis of variance followed by Tukey post hoc test (α = .05) were used.

RESULTS

The SS (Ph: 12.6 MPa; Ph-TC: 6.37 MPa; SA: 11.8 MPa; SA-TC: 9.37) and SSP (Ph: 10.4 MPa; Ph-TC: 5.82 MPa; SA: 10.4 MPa; SA-TC: 10.0) surface treatments produced the highest surface roughness values (P < .001). The SS samples achieved the highest immediate bond strength for both resin cements. However, after TC, SA resin cement associated with any surface treatment produced the highest bond strength values.

CONCLUSION

The self-adhesive resin cement promoted higher and more stable bond strength values when associated with a surface roughening method.

Treatment of peri-implant soft tissue defects: a narrative review

Soft tissue defects around dental implants, such as papilla or volume loss, peri-implant recession and alterations of the ridge color and/or texture, lead to esthetic and functional complaints. Treatments of these defects in implants are more demanding than in teeth because peri-implant tissue exhibits different anatomical and histological characteristics. This narrative review discusses the proposed treatments for soft tissue defects around implants in the current literature. Several clinical and pre-clinical studies addressed methods to augment the quantity of the peri-implant keratinized mucosa. Autogenous grafts performed better than soft tissue substitutes in the treatment of soft tissue defects, but there is no clinical consensus on the more appropriate donor area for connective tissue grafts. Treatment for facial volume loss, alterations on the mucosa color or texture and shallow peri-implant recessions are more predictable than deep recessions and sites that present loss of papilla. Correction of peri-implant soft tissue defects may be challenging, especially in areas that exhibit larger defects and interproximal loss. Therefore, the regeneration of soft and hard tissues during implant treatment is important to prevent the occurrence of these alterations.

Diabetes and increased lipid peroxidation are associated with systemic inflammation even in well-controlled patients

BACKGROUND

The effect of the interaction between type 2 diabetes and dyslipidemia on inflammation and lipid peroxidation (LPO) has not been assessed.

AIM

To investigate whether diabetes coupled with dyslipidemia alters oxidative metabolism leading to increased LPO products and inflammatory status.

METHODS

100 patients were divided into four groups based upon diabetic and dyslipidemic status: poorly controlled diabetes with dyslipidemia (DM-PC/D), well-controlled diabetes with dyslipidemia (DM-WC/D), normoglycemic individuals with dyslipidemia (NG/D), and normoglycemic individuals without dyslipidemia (NG/ND). Plasma was evaluated for an LPO product (MDA), antioxidant levels and inflammatory cytokines.

RESULTS

Diabetics presented significantly higher levels of LPO (p<0.05) and the DM-PC/D had higher levels of proinflammatory cytokines and MDA in the plasma in comparison with normoglycemics (p<0.05). Interestingly IL1-β, IL-6, and TNF-α in DM-WC/D were not statistically different from those in DM-PC/D. Normoglycemic individuals with dyslipidemia presented significantly increased levels of IL-6 and TNF-α when compared to normoglycemic without dyslipidemia (p<0.05). MDA levels were also positively correlated with the presence of DM complications (r=0.42, p<0.01).

CONCLUSIONS

These findings show that dyslipidemia is associated with an increased inflammatory status, even in well-controlled diabetics and in normoglycemics. Our results suggest that lipid metabolism and peroxidation are important for the development of inflammation, which is elevated in several complications associated with diabetes.

Semidirect Restorations in Multidisciplinary Treatment: Viable Option for Children and Teenagers

Due to the esthetic necessity required nowadays, the multidisciplinary treatment became a fundamental step in the restoration success. When the patient exhibits dental agenesis of one or more elements, he can show difficulty in social interactions. The age of the patient is a limiting factor to esthetic procedures, however, it should be evaluated as a real indicative with each case. The utilization of semi-direct restorations is a viable option due the cost, esthetic and improvement of physical and mechanical properties. The purpose of this paper is to present a case detailing the confection and cementation of anterior semi-direct restorations aimed at an anatomic reestablishment associated with integrated treatment with periodontics and orthodontics.

Effects of the long-term administration of alendronate on the mechanical properties of the basal bone and on osseointegration

OBJECTIVE

To evaluate the effect of the long-term administration of alendronate on the mechanical properties of the basal bone and on osseointegration.

MATERIAL AND METHODS

One hundred and sixty female rats were randomly allocated into two equally sized groups: the control (CTL) group, which received the subcutaneous administration of saline solution, and the alendronate (ALD) group, which received the subcutaneous administration of alendronate (1 mg/kg/week). After 120 days of these therapies, one implant was placed in each rat tibia. Ten animals in each group were euthanized at 5, 10, 15, 20, 25, 30, 45, or 60 days after surgery. The tibias with implants evaluated regarding the removal torque, bone-implant contact (BIC), the bone area fraction occupancy (BAFO), and Ca/P ratio. The femurs were evaluated regarding bone mineral density (BMD) and using mechanical tests to evaluate the maximal force of fracture, stiffness, and tenacity.

RESULTS

The ALD group presented statistically significant higher BMD (all periods except 15 days), maximal force of fracture (at 20, 30, and 45 days), tenacity (at 10, 20, 30, and 45 days), stiffness (45 days), removal torque (at 20, 25 and 30 days), BIC (at 20 and 60 days), and BAFO (at 20, 30, and 45 days) than the CTL group. No differences were found between the groups regarding the Ca/P ratio.

CONCLUSION

Previous long-term therapy with alendronate caused an increase in the BMD, maximal force of fracture of the bone without changing the inorganic composition and elastic deformability of this tissue. Furthermore, the ALD therapy enhanced osseointegration.

Conservative treatment of intraosseous hemangiomas in the mandible: case report with a 17-year follow-up period

Intraosseous hemangiomas in the jaws are rare lesions and may lead to several complications. The authors present a case of a 12-year-old girl with a radiolucent periapical lesion between tooth 35 and 36 where nocturnal exsanguinating bleeding started to occur from periodontal sulcus during orthodontic treatment. Diagnosis of an intraosseous hemangioma in the mandible was based on positive needle aspiration for blood, computed tomography and arteriography. At first the family chose to only follow-up the lesion but episodes of nocturnal hemorrhage were becoming more frequent and a treatment was requested. Embolization and dental extraction were performed in order to treat the lesion. After a follow-up period of 17 years no more cases of hemorrhage occurred and lesion regressed.

Influence of disinfection with peracetic acid and hypochlorite in dimensional alterations of casts obtained from addition silicone and polyether impressions

Dental impressions disinfection is important to reduce the risk of cross contamination but this process may produce dimensional distortions. Peracetic acid is a disinfectant agent with several favorable characteristics yet underutilized in Dentistry. The aim of this paper is to compare the dimensional stability of casts obtained from addition silicone and polyether impressions that were immersed for 10 minutes in a solution of 0.2% peracetic acid or 1% sodium hypochlorite. Sixty samples in type IV gypsum were produced after a master cast that simulated a full crown preparation of a maxillary premolar. Samples were divided in 6 groups (n = 10) according to the impression material and disinfection agent: Group AC--addition silicone control (without disinfectant); Group APA--addition silicone + 0.2% peracetic acid; Group AH--addition silicone + 1% sodium hypochlorite; Group PC--polyether control (without disinfectant); Group PPA--polyether + 0.2% peracetic acid; Group PH--polyether + 1% sodium hypochlorite. Cast height, base and top diameter were measured and a mean value was obtained for each sample and group all data was statistically analyzed (ANOVA, p < 0.05). There was not a significant statistical difference between addition silicone and polyether impressions regardless of the disinfectant materials. It can be concluded that disinfection with the proposed agents did not produce significant alterations of the impressions and the peracetic acid could be considered a reliable material to disinfect dental molds.

Comparação in vitro da eficácia de diferentes formulações do gel de EDTA 24% no condicionamento da superfície radicular

INTRODUÇÃO: A biomodificação radicular visa a alterar a superfície radicular para auxiliar no reparo das estruturas periodontais de suporte destruídas pela doença periodontal. OBJETIVO: Avaliar por meio de microscopia eletrônica de varredura a eficácia do condicionamento químico com gel de EDTA 24% na remoção de smear layer e na exposição de fibras colágenas, verificando-se diferentes marcas comerciais, modos e tempos de aplicação. MATERIAL E MÉTODO: Um total de 225 amostras foram obtidas e distribuídas aleatoriamente em cinco grupos: soro fisiológico (controle); EDTA 24% (Farmácia Santa Paula); EDTA-T 24% (Farmácia Santa Paula); EDTA 24% (PrefGel; Straumann); EDTA 24% (Biodinâmica). As amostras de cada grupo foram redistribuídas aleatoriamente em subgrupos (n = 5) e condicionadas com os diferentes géis de EDTA nos tempos de 1, 2 e 3 minutos, e nos modos de aplicação tópica, fricção vigorosa e fricção suave. Os testes de Kruskal-Wallis e Dunn (p < 0,05) foram utilizados e aplicados separadamente para os fatores: marca comercial, tempo e modo de aplicação. RESULTADO: A análise estatística revelou que o gel de EDTA 24% da Biodinâmica promoveu a menor remoção de smear layer. Não foram detectadas diferenças estatísticas para os tempos de aplicação. O modo de aplicação fricção suave resultou em menor quantidade de smear layer residual. CONCLUSÃO: Todos os géis de EDTA 24% utilizados foram eficazes na remoção de smear layer e na exposição de fibras colágenas, independentemente do tempo de aplicação; no entanto, o modo de fricção suave foi mais efetivo. Na análise comparativa entre os produtos, o EDTA da Biodinâmica foi menos efetivo, já que promoveu menor remoção de smear layer e exposição de fibras colágenas.

[Useful phenotypic characteristics for presumptive identification of Candida guilliermondii]

Candida guilliermondii developed a pink-purplish colony on CHROMagar Candida. In the micromorphology in milk-tween 80 1% agar at 28 degrees C after 48 h of incubation C. guilliermondii showed small (3-5 microm), spherical yeasts without pseudohyphaes. This Candida species presented a characteristic cluster of blastospores with pseudohyphaes radiating from the centre at 96 h. The trehalose-sucrose assimilation assay was applied to the C. guilliermondii isolates which proved negative for trehalose and positive for sucrose. These results allowed for the presumptive identification of C. guilliermondii. The results were concordant in 100% of the isolates with the identification of the C. guilliermondii species by the ID 32C and Vitek YBC methods. Such automated methods offered Candida famata as a second option, with a reliability percentage of 10%. Micromorphological studies increase yeast identification reliability, especially among species presenting similar biochemical profiles.